Royal Navy Ship HMS Royal Oak sweetheart brooch

A rare First World War period H.M.S. Royal Oak gilt and enamel naval sweetheart brooch. Very good condition, original pin fittings, no damage to the enamel.
Width 37mm.
Height 19mm.
HMS Royal Oak a Revenge-class battleship was launched in 1914, on 14 October 1939 she was torpedoed and sunk by the German submarine U-47 whilst anchored at Scapa Flow in Orkney Scotland.